Pavement



R. M. COOLEY.

PAVEMENT.

, APPLICATION man DEC. H, I920.

Patented Apr. 4, 1922.

RALPH M. CGOLEY. 3F STflEAUL, MINNESOTA.

PAVEMENT.

Specification of Letters Patent.

Patented Apr. 4., H122,

Application filed December 11, 1920. Serial No. 429,886.

To all whom it may concern:

Be it known that I, RALPH M. tlooL'nr, a citizen of the United States, residing at St. Paul, in the county of Bar. and State of Minnesota, have invented a new and useful Pavement, of which the following is a specification.

My invention is an improvement in pavements and has, among its objects, to provide a pavement composed Off pre-cast block or slab elements made of plastic material capable of hardening, having interlocking tongues and grooves and tie-rods disposed transversely through said elements and adapted to assist in holding the blocks in position.

A further object is to provide, in a structure of this kind, means for permitting expansion and contraction of the various members without cracking or disrupting any portion of the pavement during cold and hot temperatures.

In the accompanying drawing, forming part of. this specification, Figure l is a plan view of a portion of my improved pavement; Fig. 2 is a section of one of the block or slab elements taken on the line 22 of Fig. 1; F ig. 3 is another section of one of the block or slab elen'ients taken on the line 33 of Fig. l 5, Fig. his a perspective view of one of the block or slab elements, and Fig. 5 is an elevation of a small portion of one of the sides of the pavement, showing one of the tie-rods before the recess in the side of the pavement has been closed.

In an embodiment of my invention, the pavement is composed oi pie-cast oblong blocks or slabs A made out of plastic material capable of hardening and laid lengthwise longitudinally of the road on a prepared sub-grade or bed B or" sand, or other suitable material, with the joints or. one row broken relative to the joints of the opposite row. The blocks or slabs are cast with interlocking tongues C and grooves D, both on the adjacent sides and adjacent ends, the outermost side edges of the pavement being left even and tree from tongues and grooves.

The tongues are preterably about one-half the thickness oi the block or slab and the lower projection or side E of the groove extends well underneath the body of the adjoining blocks or slab to give additional support. The extra thickness also commences well underneath and back of the grooved edge of the block or slab to increase strength.

Sleeves or bushings F are cast in the center of the blocks or slabs running horizontallyfthrough and extending from one side of the pavement to the other, thus forming a chainof conduits, there being one section in each block or slab. The section of sleeves or V bushings oi? a block or slab is made to project into. the adjoining block or slab, there being an oval space left at G where the sleeve or bushing enters. This space is so cast that there is permitted a slight amount of play longitudinally between two adjoining blocks or slabs, but no play transversely. The sleeve or bushing sections are placed end to end across the pavement at as frequent intervals through the blocks or slabs as desired so that when all of the blocks or slabs are laid, there is a clear 7 opening through each row of sleeves or bushings across the entire width of the pavement. Through'this opening a tiered H is bolted so that all of the blocks or slabs of the transverse cross sections of the pavement are drawn together tight. The rod or bolt H is smaller in diameter than the opening in the sleeves or bushings ior contraction and expansion, due to weather conditions. The side or end of a block or slab, which constitutes'the side or end of. the pavement, is neither tongued nor grooved, but may, as shown in Figs. 1 and 5, be cast with an even straight edge. At the conduit ends'in the side edges, a space or recess I is cast, allowing the burrs J on the tie-rods to be counter sunk. The remaining space may be filled either with grout or bituminous material.

The longitudinal joints between the blocks or slabs, after being laid and tied together in the manner stated, may be filled with either grout or bituminous material and the transverse joints preferably may be filled with bituminous material in order that the necessary contraction and expansion may take place. 7

Among some of the features of advantage attained by my invention, it may be mentioned that the improved pavement does away with all wavy surfaces frequently found in other pavements, due to consistency of the plastic material, to uneven forms, and to the effect of gravity. It obviates cracks due to contraction in setting and to changes of temperature after completion. It allows a ready means for future widening and facilitates repairs. It also does not block traffic from passing over im- .mediately after it is laid. The method of tying the blocks or slabs together prevents them from sliding either laterallyor longitudinally, thus avoiding all broken joints and allowing for contraction and expansion. The re-entorcing of the joints prevents one slab or block from heaving up above the rest and prevents breaking or chipping of the edges. My improved pre-cast pavement also insures greater safety in driving by defining absolutely the center of thepavement by means of the longitudinal joints, Whichis particularly advantageous for the driver in the glare of head lights of an approaching car.

Changes in the specific form of my invention, as herein disclosed, may be made within the scopelof what is claimed Without de )arting from the spirit of my invention.

'Iaving described my invention, what I.

claim as new and desire to secure by Letters Patent is: r

'1. A pavement composed of pre-cast block or slab elements of plastic material capable of hardening, each adjacent pair of said elements having tongue and groove joints, the lower side of the groove of the joint being constructed wholly below and integral withthe body of one element and projecting well underneath to form an increased support for the body of the adjoining element.

2. A pavement composed of pre-cast'block or slab elements of plastic material capable of hardening, each pair of said elements having intermeshing tongue and groove joints re-enforced by an integral projection of the lower side of the groove extending well underneath the adjoining element and the extra thickness, also, commencing well underneath the grooved edge of the grooved element. V

3. A pavement including blocks arranged in such relation that the joints between the sam are. broken, composite conduits extending through said blocks and comprising numbers of hollow reinforcing sections arranged end to end, each section reaching from one block into the next adjacent block, and tie-rods passing through said composite conduits to secure said blocks in a unitary structure.

t. A pavement composed of pre-cast block or slab elements of plastic material ca able of hardening, said elements being he (1: at intervals by transverse tie-rods bolted therethrough and sleeve linings in said elements,

through which said rods are threaded.

in, such relation that the joints between the same are broken, tie-rods securin said blocks in a. unitary structure and rein orcing sleeve sections joining certain blocks and forming series of receiving conduits for said tie-rods, said sleeve sections being fixed against movement in the blocks to hold the bearing surfaces thereof in the same plane, but free to mov slightly in a planeiparallel with said surfaces and thereby allow for contraction and expansion of the avement.

In testimony whereof, I have signed my name to this specification.

RALPH M. COOLEYQ 

